Screen enclosures are commonly built above patios, lanais, porches, swimming pools, decks and other spaces. Such enclosures can be partially attached to a house or other building. Alternatively, the enclosure may comprise a gazebo, shelter or other free standing facility. Recently, the size and height of screen enclosures have increased dramatically. A growing number of these structures have been installed in conjunction with multi-story homes.
Virtually all conventional screen enclosures employ an extruded aluminum framework featuring vertical posts or columns and horizontal beams extending between the columns for supporting a number of screen panels. In most cases, the screen panels forming the sides of the enclosure are secured to both the upright posts set in the ground and the horizontal beams extending between the posts. In larger screen enclosures, such as those featured in multi-story homes, the screen panels form what is known as “picture windows” which can be quite expansive. Screen enclosures of this size may employ 2″×8″ or even larger carrier beams to provide the framework and overall enclosure with adequate structural strength. Properly assembling and installing the framework of these large enclosures can be particularly challenging. Conventionally, receptacles must be precisely cut in the posts to accommodate the horizontal beams. This is tedious, time consuming and very labor intensive work. If accurate measurements are not carefully taken, the framework will not fit together correctly. The beams and posts may have to be re-cut and/or reassembled. Valuable time, material and expense may be wasted. When cuts are formed in the posts for receiving the beams, there is little, if any room for error or adjustment. A measuring mistake can result in the entire process having to be repeated. Inaccuracies and miscalculations are even more commonplace when inexperienced installers perform the work. Even if measurements and cuts are made accurately, the entire process of mounting the extruded beams to the posts of the enclosure tends to require an inordinate amount of time and effort. This translates to increased construction costs.
The particular horizontal beams presently utilized to form picture windows in larger screen enclosures exhibit additional disadvantages. These oversized extruded beams, which may be 2″×8″, 2″×9″ or 2″×10″ in size, normally comprise two opposing extruded half pieces, each of which includes a wide or broad surface forming a respective face of the beam and a pair of relatively narrow legs extending perpendicularly from the wide surface. When the two half pieces are joined together, the opposing pairs of legs overlap and interconnect to form top and bottom sides of the finished beam. Conventionally, spline grooves are formed in the narrow legs and thereby in the top and bottom sides of the beams. These grooves receive elastomeric splines to attach the screen panels to the beams. The spline grooves have heretofore been formed in the top and bottom sides because the pieces used to form the beams have also traditionally been utilized for forming roof rafters and vertical uprights. However, that placement of the grooves is problematic when the beams are used to support the “picture window” screen panels that define the sides of the larger enclosures. In order to properly support the screen panels in such structures, the spline grooves should ideally be formed in the broad, outwardly facing vertical surface of the assembled beam rather than the narrow upper and lower side surfaces. Otherwise, the screen is apt to be too easily dislodged from the beam by high winds or other adverse weather conditions.
In an attempt to overcome the foregoing problem, screen enclosure installers have previously added an extruded. L-shaped 1″×2″ attachment piece to the narrow top side of the assembled beam. The 2″ leg of the attachment is engaged with the 2″ side surface of the beam. The 1″ leg section of the attachment overlaps the wide outer face of the assembled beam and includes a spline groove that is thereby effectively formed on the preferred outer face of the beam. However, even this attempted solution has not proven to be optimally effective. For one thing, adding such an attachment to each of the horizontal beams of a large enclosure requires the expenditure of considerable time, labor and expense, which increases the cost of installing the screen enclosure considerably. In addition, the spline groove attachment itself is apt to be torn from the horizontal beam by high winds of the type that are frequently encountered in tropical locations where large or oversized screen enclosures are often installed. This can cause serious damage to the enclosure, which may be expensive and time consuming to repair.